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Questions on Gelcoat fiberglass.


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I looked at this boat today.   There is a gouge about 8cm long that took off the gelcoat down to the fiberglass and another 20cm or so of scratch.   The owner said it doesn't leak and it happened last weekend when he bumped his trailer.  I see some quick fix type kits avail online to fill things like this but then again I've seen some videos of boat repairs which were more involved.  I'm sure some of you have done similar unfortunately.   I'm curious how you repaired and at what sort of cost?   I haven't purchased this boat but it in all other ways looks to be the one,, 

 

Bear

 

 

Edited by Noo2OzFish
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you can buy small fiberglass repair kits..resin and mat inc...cut up mat splash resin in there wit brush and shove some mat in..it may take three or four fills  thelast coat mix white paint in resin then sand back when done..you can buy fiberglass bog in small tins an fill hole with that first..rick

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Hi Bear,

From the picture it looks like the damage happened near the bow... this is one of the strongest parts of the hull with the most fglass layers so I doubt any structural damage has occurred that would require more than gelcoat repair.

Gelcoat is the cosmetic and waterproof layer that sits on top of the fglass (its the fglass which provides the strength and structure). Repairing Gelcoat is fairly simple. However, if the underlying fglass was damaged then it would be much more complex involving opening up the glass to further expose the fglass strands, using fglass cloth/chopped strand + resin to rebuild the structure, and then topcoating with gelcoat/flowcoat. (pretty much what rick described previously).

Gelcoat chips are common on fglass boats. I have repaired mine in the past with this product - available from Whitworths, SupeGelcoat filler.jpgrcheap Auto etc.

The process is to wash down the area and exposed fglass with acetone and let it dry. Then follow the instructions on how to mix and apply the repair filler.  Sand / cut / polish the final surface once set. (When I started I experimented by mixing a small batch just to see how the stuff behaved and how quickly it set. )

Final comment, if that damage was on the transom, I would be much more interested in how long it had been left like that - especially submerged. Most transoms are constructed with plywood sandwiched between fglass/gelcoat layers. The underlying fglass (usually polyester resin)  can hold water and hence the transom plywood may have got damp...and you don't want that.

Cheers

Zoran

 

 

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2 hours ago, zmk1962 said:

Hi Bear,

From the picture it looks like the damage happened near the bow... this is one of the strongest parts of the hull with the most fglass layers so I doubt any structural damage has occurred that would require more than gelcoat repair.

Gelcoat is the cosmetic and waterproof layer that sits on top of the fglass (its the fglass which provides the strength and structure). Repairing Gelcoat is fairly simple. However, if the underlying fglass was damaged then it would be much more complex involving opening up the glass to further expose the fglass strands, using fglass cloth/chopped strand + resin to rebuild the structure, and then topcoating with gelcoat/flowcoat. (pretty much what rick described previously).

Gelcoat chips are common on fglass boats. I have repaired mine in the past with this product - available from Whitworths, SupeGelcoat filler.jpgrcheap Auto etc.

The process is to wash down the area and exposed fglass with acetone and let it dry. Then follow the instructions on how to mix and apply the repair filler.  Sand / cut / polish the final surface once set. (When I started I experimented by mixing a small batch just to see how the stuff behaved and how quickly it set. )

Final comment, if that damage was on the transom, I would be much more interested in how long it had been left like that - especially submerged. Most transoms are constructed with plywood sandwiched between fglass/gelcoat layers. The underlying fglass (usually polyester resin)  can hold water and hence the transom plywood may have got damp...and you don't want that.

Cheers

Zoran

 

 

When i got my boat it had a few chips in it and I did the same as what Zoran has said.  Bought some gel coat putty and a catylyst from a fibreglass store.  Mixed it 100g to 1ml, filled the chips and sanded back.

 

Just curious, the reason I didnt go with the Septone filler was it says on the tin  

" NOTE: Not suitable for use below the water line unless the surface is sealed with the appropriate top coat. "

Have you used yours below the waterline without any issue Zoran?

 

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Hi Fishop,

My tin is several years old and does not have that warning (I've read it 4 times now!!). Maybe Septone changed the formula - perhaps they have switched to a cellulose thickener to make it easier to sand - the cellulose may absorb water. I guess a call to the distributor in Australia should sort this out. Good catch if they have changed it - thanks !

BTW yes I have used it below the water line... no issues so far... my boat is not moored....so it is in the water max 48hrs continuous.

Attaching photos of my tin and the labels next.

Cheers

Zoran

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I can make out ABG400 on the side of my tin (second last picture I posted just above the barcode)... so its the same product part number but earlier manufacturing date. I bought mine from Bias marine just before they shut doors - perhaps 3+yrs old now. The tin picture from the website has something written in the aqua coloured box below Septone... can't quite make it out...

Logo.jpg

 

But it looks like they have made some product changes and the new product has the below waterline restriction. Good Catch Fishop !

So back to Bears question... to fix the gelcoat gouge, the process is as discussed ... you will need a gelcoat putty (read the product fine print) or you can mix your own: flowcoat + something like AEROSIL filler (to make it a paste and non sag for vertical surfaces). They are all relatively in-expensive.

Cheers

Zoran

 

 

 

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On 11/10/2017 at 4:17 PM, Fishop said:

I got mine from fibre finish in townsville.  I might still have the receipt at home I can confirm what the product was.

Flowcoat was what they gave me last time. 

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